////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2011-2021 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <QScrollBar>

#include "Container.h"
#include "SliderControl.h"
#include "QtHandlesUtils.h"

#include "octave-qobject.h"

#include "graphics.h"
#include "interpreter.h"

#define RANGE_INT_MAX 1000000

namespace octave
{

  SliderControl*
  SliderControl::create (octave::base_qobject& oct_qobj,
                         octave::interpreter& interp,
                         const graphics_object& go)
  {
    Object *parent = parentObject (interp, go);

    if (parent)
      {
        Container *container = parent->innerContainer ();

        if (container)
          return new SliderControl (oct_qobj, interp, go,
                                    new QScrollBar (container));
      }

    return nullptr;
  }

  SliderControl::SliderControl (octave::base_qobject& oct_qobj,
                                octave::interpreter& interp,
                                const graphics_object& go,
                                QAbstractSlider *slider)
    : BaseControl (oct_qobj, interp, go, slider), m_blockUpdates (false)
  {
    uicontrol::properties& up = properties<uicontrol> ();

    slider->setTracking (false);
    Matrix bb = up.get_boundingbox ();
    bool vertical_slider = ( bb(2) < bb(3) );
    slider->setOrientation (vertical_slider ? Qt::Vertical : Qt::Horizontal);
    if (vertical_slider)
      slider->setInvertedAppearance (true);  // Matlab compatibility
    Matrix steps = up.get_sliderstep ().matrix_value ();
    slider->setMinimum (0);
    slider->setMaximum (RANGE_INT_MAX);
    slider->setSingleStep (octave::math::round (steps(0) * RANGE_INT_MAX));
    slider->setPageStep (octave::math::round (steps(1) * RANGE_INT_MAX));
    Matrix value = up.get_value ().matrix_value ();
    if (value.numel () > 0)
      {
        double dmin = up.get_min (), dmax = up.get_max ();

        slider->setValue (octave::math::round (((value(0) - dmin) / (dmax - dmin))
                                               * RANGE_INT_MAX));
      }

    connect (slider, &QAbstractSlider::valueChanged,
             this, &SliderControl::valueChanged);
  }

  SliderControl::~SliderControl (void)
  { }

  void
  SliderControl::update (int pId)
  {
    uicontrol::properties& up = properties<uicontrol> ();
    QScrollBar *slider = qWidget<QScrollBar> ();

    switch (pId)
      {
      case uicontrol::properties::ID_SLIDERSTEP:
        {
          Matrix steps = up.get_sliderstep ().matrix_value ();

          slider->setSingleStep (octave::math::round (steps(0) * RANGE_INT_MAX));
          slider->setPageStep (octave::math::round (steps(1) * RANGE_INT_MAX));
        }
        break;

      case uicontrol::properties::ID_VALUE:
        {
          Matrix value = up.get_value ().matrix_value ();
          double dmax = up.get_max (), dmin = up.get_min ();

          if (value.numel () > 0)
            {
              int ival = octave::math::round (((value(0) - dmin) / (dmax - dmin))
                                              * RANGE_INT_MAX);

              m_blockUpdates = true;
              slider->setValue (ival);
              m_blockUpdates = false;
            }
        }
        break;

      default:
        BaseControl::update (pId);
        break;
      }
  }

  void
  SliderControl::valueChanged (int ival)
  {
    if (! m_blockUpdates)
      {
        gh_manager& gh_mgr = m_interpreter.get_gh_manager ();

        octave::autolock guard (gh_mgr.graphics_lock ());

        graphics_object go = object ();

        if (go.valid_object ())
          {
            uicontrol::properties& up = Utils::properties<uicontrol> (go);

            Matrix value = up.get_value ().matrix_value ();
            double dmin = up.get_min (), dmax = up.get_max ();

            int ival_tmp = (value.numel () > 0 ?
                            octave::math::round (((value(0) - dmin) / (dmax - dmin))
                                                 * RANGE_INT_MAX) :
                            0);

            if (ival != ival_tmp || value.numel () > 0)
              {
                double dval = dmin + (ival * (dmax - dmin) / RANGE_INT_MAX);

                emit gh_set_event (m_handle, "value", octave_value (dval));
                emit gh_callback_event (m_handle, "callback");
              }
          }
      }
  }

}
